Field of the Invention
The present invention relates generally to patient care devices and more particularly to a novel moisture sensing and elevated temperature indicating device. The combined apparatus of the invention continuously monitors the patient's temperature and senses urination in clothing articles such as diapers worn by young children and/or incontinent adults, respectively, and for emitting alarm signal(s) to alert a caregiver that a diaper change is needed.
Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Bladder incontinence is a problem endemic in the very young and is cured only by intensive training as the young child goes through its second and third year of life requiring in the meantime, the constant use of diapers. The same problem can affect the elderly or the infirm or persons of any age who may have this problem because of physiological or psychological problems. A problem of this nature may be a major source of embarrassment. The mere fear of such incontinence can be a danger to the psychological welfare of persons already subject to severe psychological pressures due to other infirmities. Such people, both the very young and the infirm, often have no warning that their undergarments are being wet by urine until the undergarments are uncomfortably wet. There has always been a need for a device which can automatically warn either the person involved, or his/her caretaker (nurse or parent) that such undesirable leakage or wetness has occurred.
Various devices for detecting moisture or wetness such as caused by urination are known in the prior art. In diapers, the purpose of such devices is to set off an alarm when the diaper becomes wet. This permits a parent or other attendant to immediately tend to a newborn infant, toddler or an incontinent adult. Such devices usually include a pair of electrodes placed in the diaper which conduct electric current if wetness is detected. Prior art devices of this type, however, have numerous disadvantages such as requiring current-carrying conductors to pass mechanically through the diaper's plastic outer sheath, which may subject the skin of the child/incontinent adult to potentially high voltages, may be sensitive only in a limited area in the diaper, may accidentally respond to the wearer sitting on a wet or metal bench or park slide or may have other undesirable drawbacks.
The numerous disadvantages of the prior art urine sensing devices have been largely overcome by the highly novel and useful apparatus illustrated and described in U.S. Pat. No. 6,559,772 issued to the inventor named herein. As will become apparent from the discussion which follows, the novel and useful apparatus described in this patent has now been improved by the addition of novel means for continuously monitoring the temperature of the patient while at the same time standing ready to automatically alert a caregiver that a diaper change is needed.
Similarly, a wide variety of temperature sensing devices that operate on several different scientific principles have been suggested in the past. By way of example, one type of prior art thermometer uses thermochromic liquid crystals that are constructed in a planar shape and react to changes in temperature by changing color. This type of thermometer is discussed in U.S. Pat. No. 6,241,386 issued to Limburg et al. As discussed in this patent, thermochromic liquid crystals are typically made of twisted molecular structures comprising optically active mixtures of organic chemicals and include cholesteric compositions, chiral nematic formulations, and combinations of the two. Such crystals have been implemented in a variety of forms. One of the most prevalent examples is a temperature strip made by placing numerous thermochromic liquid crystal rectangles end to end. The rectangles are arranged so that, as the ambient temperature changes from lowest to highest readable temperature, the rectangles are individually illuminated sequentially from one end of the strip to the other.
Another prior art product that displays a change responsive to changes in temperature is discussed in U.S. Pat. No. 4,744,113 issued to Kogut. This product concerns a toilet training aid having a porous sheet of paper with an invisible picture thereon that is placed over a toilet bowl and produces an image when wetted by warm liquid.
In a similar vein, U.S. Pat. No. 4,725,462 issued to Kimura concerns the use of heat activated indicia on textiles. More particularly, Kimura uses thermochromatic colors formed into a textile to form an image. The indicia is not visible to the naked eye in the normal ambient temperatures but when subjected to a predetermined temperature, such as when immersed in bath water, an image appears to the user.